God's forgiveness is based on the payment for sin made by His son on the cross. Go to the cross of Christ for your own forgiveness then many of your questions will find their answer...or never need to be asked.
For those whom God has forgiven much through the death of His Son, then, as God has forgiven us, we ought also to forgive one another.
"Be kind to one another, tenderhearted, forgiving one another, as God in Christ forgave you." Ephesans 4:32
As for Jimmy Swaggert, he has done nothing to me so their is no need for me to forgive him. It is God that each of us needs forgiveness from.